Selection and characterization of hepatitis C virus replicons dually resistant to the polymerase and protease inhibitors HCV-796 and boceprevir (SCH 503034).
HCV-796 is a nonnucleoside inhibitor of the hepatitis C virus (HCV) nonstructural protein 5B (NS5B) polymerase, and boceprevir is an inhibitor of the NS3 serine protease. The emergence of replicon variants resistant to the combination of HCV-796 and boceprevir was evaluated. Combining the inhibitors greatly reduced the frequency with which resistant colonies arose; however, some resistant replicon cells could be isolated by the use of low inhibitor concentrations. These replicons were approximately 1,000-fold less susceptible to HCV-796 and 9-fold less susceptible to boceprevir. They also exhibited resistance to anthranilate nonnucleoside inhibitors of NS5B but were fully sensitive to inhibitors of different mechanisms: a pyranoindole, Hsp90 inhibitors, an NS5B nucleoside inhibitor, and pegylated interferon (Peg-IFN). The replicon was cleared from the combination-resistant cells by extended treatment with Peg-IFN. Mutations known to confer resistance to HCV-796 (NS5B C316Y) and boceprevir (NS3 V170A) were present in the combination-resistant replicons. These changes could be selected together and coexist in the same genome. The replicon bearing both changes exhibited reduced sensitivity to inhibition by HCV-796 and boceprevir but had a reduced replicative capacity.
Flint
Mike
M
Wyeth Research, Pearl River, NY 10965, USA. flintm@wyeth.com
Mullen
Stanley
S
Deatly
Anne M
AM
Chen
Wei
W
Miller
Lynn Z
LZ
Ralston
Robert
R
Broom
Colin
C
Emini
Emilio A
EA
Howe
Anita Y M
AY
D000998:Antiviral Agents / Q000494:pharmacology*; D001572:Benzofurans / Q000494:pharmacology*; D002460:Cell Line; D003001:Cloning, Molecular; D024882:Drug Resistance, Viral / Q000235:genetics*; D018274:Electroporation; D014644:Genetic Variation; D016174:Hepacivirus / Q000187:drug effects* / Q000235:genetics*; D006801:Humans; D007372:Interferons / Q000494:pharmacology; D016296:Mutagenesis / Q000187:drug effects; D009154:Mutation / Q000235:genetics; D019384:Nucleic Acid Synthesis Inhibitors; D011392:Proline / Q000031:analogs & derivatives* / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology*; D012367:RNA, Viral / Q000096:biosynthesis / Q000235:genetics; D012093:Replicon / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013449:Sulfonamides / Q000494:pharmacology*
D000998:Antiviral Agents; D001572:Benzofurans; C539481:HCV 796; D019384:Nucleic Acid Synthesis Inhibitors; D011480:Protease Inhibitors; D012367:RNA, Viral; D013449:Sulfonamides; C512204:N-(3-amino-1-(cyclobutylmethyl)-2,3-dioxopropyl)-3-(2-((((1,1-dimethylethyl)amino)carbonyl)amino)-3,3-dimethyl-1-oxobutyl)-6,6-dimethyl-3-azabicyclo(3.1.0)hexan-2-carboxamide; D007372:Interferons; D011392:Proline